1. Field of the Invention
The present invention relates generally to congestion control during data transfer and, more particularly, to systems and methods for dropping data using a drop profile.
2. Description of Related Art
Conventional network devices, such as routers, relay streams of data through a network from a source to a destination. Typically, the network devices include one or more memory subsystems to temporarily buffer data while the network devices perform network-related functions, such as route processing or accounting.
A data stream may be considered a pipe of data packets belonging to a communication between a particular source and a particular destination. A network device may assign a variable number of queues (e.g., where a queue may be considered a logical first-in, first-out (FIFO) buffer) to a data stream. For a stream with n queues, the relationship of queues and streams may be represented by:
      stream    bandwidth    =            ∑      0              n        -        1              ⁢                  ⁢                  queue        bandwidth            .      
A problem that may arise in the use of queues is that congestion occurs if data builds up too quickly in the queues (i.e., data is enqueued at a faster rate than it is dequeued). Network devices typically address this problem by notifying sources of the packets of the congestion. This notification sometimes takes the form of dropping more recent packets received from the sources. It is sometimes a difficult and time-consuming process, however, to decide whether to drop a packet from a queue.
Therefore, there is a need for efficient mechanisms for determining whether to drop data from a queue.